I have a 97 F150 StepSide 4x4 4.6. 181k miles. Had it for 3 days and already have a bunch of issues. For one it has a cylinder 4 misfire. I did a coolant flush. Drained old coolant (brown as hell reservoir was all dirty) and put distilled water and flush thru it. Went to go drive it. No issues. Got home drained it out and refilled with clean brand new coolant. Went to go drive it and MASSIVE amounts of white smoke. Parked it. Came back several hours later and test drove it again. Massive white smoke again for about 2 miles then it went away. Heat went from super hot to cold for about a mile then back to super hot again. Temp gauge is normal. No milky oil etc. Parked it came back 20 mins later and started it. White smoke again seems to be more amounts when I use the throttle... Just bought it and love the truck but don't want to finance 3k and have to do a head gasket on top of it... HELLLLPPPP!!!

 

Did you not drive it before you bought it? It needs head gaskets or the head or block is cracked. If you don't want to put any more money in it you could try some head gasket sealer and hope for the best.

 

Yes I did test drive it and basically do an entire bumper to bumper inspection. Even brought my temp gun and everything read normal. There wasn't a misfire no smoke nothing... Just drove it to the dealer (30 miles) only had white smoke for about a mile. Temp gauge normal. Either I get my old car and cash back or they will fix it... Haven't even had the truck 2 days...

 

Yea, take it back, the sooner the better.

 

Took it to the dealer this morning. Told them I had a guy look at it and diagnose the misfire and then all of this started happening. The guy who looked at it is a Ford Master Tech 20+ years. Told the mechanic at the dealer about it having 16 CEL codes (tho it has a paper in the car saying it passed NC inspection 🤔 ) told him about that and then all of the issues in the main post. Got the feeling that this mechanic doesn't like to be told he is wrong. Gave me a loaner car with a dealer plate to get around on until they figure out if it's worth fixing or not . Will post results when I know.

Note had the following list of codes:

P0401 (3 Codes)
P0304 (4 Codes)
P0171 (4 Codes)
P0174 (5 Codes)

 

Also also probably worth mentioning I asked around about it before but I put a can of seafoam in the gas tank right after I bought it and filled up the gas tank so could that be what caused the smoke even a day or two after I filled up?

 

I wouldn't think so, no.

 

Ah was just wondering because I had seen similar results for a few different people on YouTube. Dealer emailed me yesterday said that they let it idle for 5 to 6 hours and it didn't go over halfway on the temp gauge no coolant leaking and did a compression test as well that was fine. Did say there was a clog that contributed to the misfire (eye roll) still don't feel like it's been a hundred percent resolved :/